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• Crystal plasticity finite element model exhibits higher accuracy in evaluation of surface roughness and thickness distribution of cups fabricated by micro deep drawing. • The magnitude of surface roughness S z is almost linearly dependent on the average grain size of austenitic stainless steel foils. • The brass components are beneficial to the formation of drawn cups with uniform thickness distribution and the absence of severe defects. The present work involves the numerical simulation and experimental study on the surface roughness evolution and heterogeneous plastic deformation (strain localization and concomitant surface morphology evolution) in grain scale of micro deep drawn parts of austenitic stainless steel (ASS) 304 foils. A three-dimensional modeling framework was used to simulate the micro deep drawing (MDD) process. The simulation involved the development of a Voronoi-based polycrystalline geometry model (VPGM), a multi-stress-strain response model, and a crystal plasticity finite element methods (CPFEM) model. The results indicate that CPFEM model exhibits higher accuracy in the localized stress and strain, thickness distribution fluctuation and surface roughness evolution of the fabricated parts compared to multi-stress-strain response model. Therefore, the plastic deformation heterogeneity in MDD is in-depth discussed based on CPFEM model. The results show that the coarse-grained foils correspond to the intense strain localization, which is the main cause of surface roughening. Considering the average grain size is close to the thickness of ASS foils, mounding features on the rough surface may readily develop further into potentially fractured sites during deformation. On the other hand, crystal orientation influence plastic deformation by affecting the slip behavior of materials. The effect of crystal orientations including {011} 〈211〉 (Brass), {011} 〈100〉 (Goss), and {112} 〈110〉 components on deformation is discussed. The results indicate a strong correlation between the magnitude of the Schmid's factor and the ease of deformation. Additionally, variations in Schmid's factor across different directions result in differences in deformation accumulation, which affects the thickness distribution along the radial direction and the distribution of earrings and wrinkles along the circumferential direction of the fabricated micro parts. [ABSTRACT FROM AUTHOR]

The deciduous tree Idesia polycarpa can provide premium edible oil with high polyunsaturated fatty acid contents. Here, we generate its high-quality reference genome, which is ∼1.21 Gb, comprising 21 pseudochromosomes and 42,086 protein-coding genes. Phylogenetic and genomic synteny analyses show that it diverged with Populus trichocarpa about 16.28 million years ago. Notably, most fatty acid biosynthesis genes are not only increased in number in its genome but are also highly expressed in the fruits. Moreover, we identify, through genome-wide association analysis and RNA sequencing, the I. polycarpa SUGAR TRANSPORTER 5 (IpSTP5) gene as a positive regulator of high oil accumulation in the fruits. Silencing of IpSTP5 by virus-induced gene silencing causes a significant reduction of oil content in the fruits, suggesting it has the potential to be used as a molecular marker to breed the high-oil-content cultivars. Our results collectively lay the foundation for breeding the elite cultivars of I. polycarpa. [Display omitted] • A chromosome-level genome of Idesia polycarpa is presented • I. polycarpa and P. trichocarpa share a common ancestor in Salicaceae family • A potential oil-content-related gene, SUGAR TRANSPORTER 5 (IpSTP5), is identified Zuo et al. report a chromosome-level genome of Idesia polycarpa , a Chinese native deciduous tree, whose fruits can be used for extracting high-quality edible oil. Further, they identify a potential oil-content-related gene, SUGAR TRANSPORTER 5 (IpSTP5), by population analysis of 42 wild accessions. [ABSTRACT FROM AUTHOR]

Dielectric elastomers (DEs) have a great potential in applications as smart materials such as artificial muscles and flexible robotics, due to their advantages of large deformation, good flexibility and fast actuation response. However, the excellent electro-actuation performance of DE materials is always achieved under high electric fields, which limits their widespread application. Herein, the synthesized acrylate-based copolymer E 8 G 2 (the molar ratio between 2-ethylhexyl acrylate and glycidyl methacrylate is 8:2) was incorporated into the polydimethylsiloxane (PDMS) matrix by solution mixing and compression molding to prepared a series of bi-network DE composites. The design of the all-organic bi-network structure not only regulates the dielectric-flexibility of E 8 G 2 /PDMS composites synchronously but also relieves the problem of plasticizer exudation. The E 8 G 2 /PDMS composites achieved a remarkable electro-actuated strain of 43.86 % at 50 V/μm, which is improved by 431.08 % compared with pure PDMS (6.95 %). Consequently, this study provides a promising approach for the preparation of advanced DE composites with outstanding electro-actuated performance in low-field driving applications. [Display omitted] • The dielectric elastomer with all-organic bi-network structures were prepared. • The electro-actuated strain of DE composite reaches 43.86 % at low-field of 50 V/μm. • The synergistic regulation on ε r and Y leads to the improved electro-actuation. • The long-standing issue of plasticizer-exudation from DE composites is relieved. [ABSTRACT FROM AUTHOR]

• Largest GBS genome sequence sample of Chinese infants. • Baseline data for GBS surveillance and vaccine impact evaluation. Group B Streptococcus (GBS) is a leading cause of morbidity and mortality in young infants worldwide. This study aimed to investigate candidate GBS vaccine targets, virulence factors, and antimicrobial resistance determinants. We used whole-genome sequencing to characterize invasive GBS isolates from infants < 3 months of age obtained from a multicenter population-based study conducted from 2015 to 2021 in China. Overall, seven serotypes were detected from 278 GBS isolates, four (Ia, Ib, III, V) of which accounted for 97.8 %. We detected 30 sequence types (including 10 novel types) that were grouped into six clonal complexes (CCs: CC1, CC10, CC17, CC19, CC23 and CC651); three novel ST groups in CC17 were detected, and the rate of CC17, considered a hyperinvasive neonatal clone complex, was attached to 40.6 % (113/278). A total of 98.9 % (275/278) of isolates harbored at least one alpha-like protein gene. All GBS isolates contained at least one of three pilus backbone determinants and the pilus types PI-2b and PI-1 + PI-2a accounted for 79.8 % of the isolates. The 112 serotype III/CC17 GBS isolates were all positive for hvgA. Most of the isolates (75.2 %) were positive for serine-rich repeat glycoprotein determinants (srr1 or srr2). Almost all isolates possessed cfb (99.6 %), c1IE (100 %), lmb (95.3 %) or pavA (100 %) gene. Seventy-seven percent of isolates harboured more than three antimicrobial resistance genes with 28.4 % (79/278) gyr A quinolone resistance determinants mutation, 83.8 % (233/278) carrying tet cluster genes and 77.3 % (215/278) carrying erm genes which mediated fluoroquinolone, tetracycline and clindamycin resistance, respectively." The findings from this large whole-genome sequence of GBS isolates establish important baseline data required for further surveillance and evaluating the impact of future vaccine candidates. [ABSTRACT FROM AUTHOR]

Floods are a great threat to Pakistan with increasing concern. As the consequences of increased extreme weather related to climate change, Pakistan experiences severe floods almost every year. This study aims to explore and analysis the actual inundated situation, magnitude, the possible causes of the 2022 devastating floods, and future trends. We presented an enhanced nationwide flood mapping method and compared with other pixel-based image processing techniques including active contours and change detection. These algorithms were applied to Sentinel-1 Ground Range Detected (GRD) Synthetic Aperture Radar (SAR) imagery (10 m spatial resolution) with various land types and inundation scenarios in Pakistan, and were evaluated using other reference flood products. Accuracy evaluation analysis demonstrated that our algorithm has high robustness and accuracy, with the overall accuracy (OA) higher than 0.83 and critical success index (CSI) up to 0.91, and is suitable for automated flood monitoring in near real time. Nearly one-third of the lands were flooded in 2022, and more than half were inundated croplands. Punjab and Sindh provinces were the most severely affected regions, with the proportions of inundated area in 2022 (21.26% and 20.55%) nearly twice of that in 2010 (11.40% and 12.70%), indicating an intensified flooding trend. Analysis of possible influential factors showed that the intense and cumulative rainfall during the monsoon season (June to August) was the major cause of the 2022 flood event. Although the snow melted rapidly in June (the average change in snow depth is ∼10 mm), the overall ablation contributed insignificant amount to the flood water. The glacial lake outburst floods (GLOFs) induced by abnormal April–May heatwave provide water flowed into the tributaries of the Indus River, but are difficult to spread for thousands of kilometers from mountains to the plain downstream. The combination of the intrinsic arid climate and extreme floods exacerbate the already severe situation. • This paper presents an automated method based on tile thresholding and fuzzy logic. • The inundation in Punjab and Sindh in 2022 are nearly twice of that in 2010. • The cumulative rainfall is the major cause of the 2022 flood event. • The snow melting and GLOFs are likely small relative to the flood water gains. • These observations imply an intensified flooding and water cycle in Pakistan. [ABSTRACT FROM AUTHOR]

This work aims to study the ammonia/methanol blended fuel with ammonia cracking in lean-burn condition. Ammonia on-line cracking to produce hydrogen production has the potential to realize the high-efficiency combustion. A new ammonia/methanol/hydrogen mechanism was updated and simplified using several reduction methods to optimize the computation time in 3D simulation. Visualization measurements in constant volume combustion chamber (CVCC) for flame propagation and NO generation were conducted, and 3D computational fluid dynamics (CFD) modeling was also established with the simplified mechanism simultaneously to investigate the impact of methanol addition and ammonia cracking in the lean-burn mode. The findings showed that methanol addition and ammonia cracking can significantly improve the combustion rate, and 60%ammonia/40%methanol with ammonia cracking ratio of 90% (N60R90) at equivalence ratio (ER) of 0.7 yields the similar LBV as pure methanol at ER of 1.0 in laminar burning condition. Its ER can be extended to 0.4 to obtain the similar level of LBV as pure ammonia at 1.0. The experiments and 3D simulations revealed that N60R90 at 0.4 yields the equivalent level of combustion rate as N60R0 at 0.8, while obtaining much lower NO emission. In addition, N60R100 at 0.4 without fuel-NO formation during the combustion can get ultra-low NO emission. This study provides the insights on low-carbon combustion strategy for ammonia cracking with low NO. [ABSTRACT FROM AUTHOR]

The chiral amine (R)-2-(1-aminoethyl)-4-fluorophenol has attracted increasing attentions in recent years in the field of pharmaceuticals because of its important use as a building block in the synthesis of novel anti-tumor drugs targeting tropomyosin receptor kinases. In the present study, a ω-transaminase (ωTA) library consisting of 21 (R)-enantioselective enzymes was constructed and screened for the asymmetric biosynthesis of (R)-2-(1-aminoethyl)-4-fluorophenol from its prochiral ketone. Using (R)-α-methylbenzylamine, D-alanine, or isopropylamine as amino donor, 18 ωTAs were identified with target activity and the enzyme AbTA, which was originally identified from Arthrobacter sp. KNK168, was found to be a potent candidate. The E. coli whole cells expressing AbTA could be used as catalysts. The optimal temperature and pH for the activity were 35–40 °C and pH8.0, respectively. Simple alcohols (such as ethanol, isopropanol, and methanol) and dimethyl sulfoxide were shown to be good cosolvents. High activities were detected when using ethanol and dimethyl sulfoxide at the concentrations of 5–20%. In the scaled-up reaction of 1-liter containing 13 mM ketone substrate, about 50% conversion was achieved in 24 h. 6.4 mM (R)-2-(1-aminoethyl)-4-fluorophenol was generated. After a simple and efficient process of product isolation and purification (with 98.8% recovery), 0.986 g yellowish powder of the product (R)-2-(1-aminoethyl)-4-fluorophenol with high (R)-enantiopurity (up to 100% enantiomeric excess) was obtained. This study established an overall process for the biosynthesis of the high value pharmaceutical chiral amine (R)-2-(1-aminoethyl)-4-fluorophenol by ωTA. Its applicable potential was exemplified by gram-scale production. • An enzymatic way for synthesizing (R)-2-(1-aminoethyl)-4-fluorophenol was reported. • 21 (R)-type ω-transaminases were screened. • Gram-scale production was achieved. • Product exhibited high (R)-enantiopurity (up to 100% e.e.). [ABSTRACT FROM AUTHOR]

• We synchronize gas hydration with membrane permeation to improve mass transfer for gas separation. • An accurate formula was developed to calculate the gas consumption during stable growth of hydrate. • We built a dynamic matching model to describe hydrate-membrane synergistic action. • We simulated the separation of H 2 -containing gas mixture by hydrate-membrane coupling method. • Simulation results indicate that the coupling method greatly improves the gas separation effect. The recovery of hydrogen (H 2) form H 2 -containing gas mixtures, such as petrochemical refinery tail gas, plays a important role in energy conservation and cost reduction. The hydrate-membrane coupling separation process has been demonstrated as a more efficient and energy-saving approach for H 2 recovery. This study aims to achieve the synergistic matching of hydration and permeation, so as to explore the underlying mechanisms of coupling and facilitate subsequent experimental studies. In this work, an effective method was developed to calculate the gas consumption rate during the stable growth stage of hydrates. Furthermore, a dynamic matching model of the hydrate-membrane coupling mechanism was employed to simulate the variations in the separation process using infinitesimal methods. The simulations indicate that the H 2 concentration of product gas and the feed gas treatment capacity of the coupling method outperform those of hydrate separation and membrane separation alone. Overall, this study provides valuable insights into an efficient and energy-saving method for H 2 recovery from H 2 -containing gas mixtures, utilizing the hydrate-membrane coupling method. These findings hold promising prospects for practical application in the future. [ABSTRACT FROM AUTHOR]

The presence of carbon tetrachloride in groundwater raises concerns for human health and the environment. Thus, there is an urgent need for a faster and more efficient groundwater remediation method. Our study found that the EHC remedial agent can achieve promising pilot remediation results quickly, as demonstrated in laboratory tests. During the pilot test, the contaminated groundwater was subjected to injection with the EHC remedial agent using in-situ high-pressure rotary jet technology. It was observed that indicators such as alkalinity and SO 4 2− can signify the occurrence of biological reduction, with the presence of ZVI significantly shortening the beginning time of biological action within the EHC. The pilot test results reveal that the initial four days following the injection of the EHC witnessed only chemical reduction, with chemical and biological reduction coexisting from day 4 to day 45. Post the 45-day mark, the removal of contaminants solely relied on biological reduction. While chemical reduction displayed a rapid rate but limited duration, insufficient for ensuring long-term effectiveness in the remediation process, bioremediation offered sustained efficacy for continuous contaminant reduction. These findings signify a more eco-friendly and efficient approach to groundwater remediation, offering both human health and environmental benefits. [Display omitted] • EHC injected using high-pressure rotary jet efficiently remediated CCl 4 -contaminated groundwater. • Alkalinity and SO 4 2− indicators demonstrated the initiation of biological reduction. • Chemical-Biological Coexistence ensure rapid and sustained remediation. • Bioremediation shows a continuous improvement in removal efficiency over 268 d. [ABSTRACT FROM AUTHOR]